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Comments 56851 to 56900:

56851. lennartvdl at 22:28 PM on 10 July 2012
       Hansen and Sato Estimate Climate Sensitivity from Earth's History
       On p.14 HS12 says: "[T]he mean sensitivity over the entire range from the Holocene to a climate just warm enough to lose the Antarctic ice sheet is almost 6°C for doubled CO2, but most of the surface albedo feedback in that range is caused by loss of the Antarctic ice sheet [...] [T]he sensitivity is smaller as climate warms from the Holocene toward a Pliocene-like climate. Thus the estimate of Lunt et al. (2010), that slow feedbacks (reduced ice and increased vegetation cover) increase the sensitivity by a factor of 1.3-1.5 is not inconsistent with the Hansen et al. (2008) estimated sensitivity." On p.15 they say: "If non-CO2 trace gases are counted as a fast feedback, the fast-feedback sensitivity becomes 4°C for doubled CO2, and the Earth system sensitivity becomes 8°C for doubled CO2 with the surface albedo feedback included [...] These sensitivities apply for today's initial climate state and negative climate forcings; they are reduced for positive forcings [...] The ultimate Earth system sensitivity includes all fast and slow feedbacks, i.e., surface feedbacks and all GHG feedbacks including CO2. Apparently Sff+sf is remarkably large in the Pleistocene for a negative forcing. No doubt that accounts for the substantial cooling of Earth in the past few million years in response to only small changes of CO2., as well as the increasingly violent glacial-to-interglacial oscillations of the late Pleistocene (Fig. 4). The Earth system sensitivity relevant to humanity now is the sensitivity of the present climate state to a positive (warming) forcing. That sensitivity is not as great as for a negative forcing, but it is much larger than the 3°C fast-feedback climate sensitivity." So do I understand correctly (from these quotes and their figure 7) that H&S think ESS for doubled CO2 over the past million years was more than 8 deg C and more than 6 deg for the current climate until all the ice has melted, after which it is reduced to somewhere between 4.5 and around 5 deg and rising again for even warmer climates? It seems I'm confusing sensitivities with and without CO2- and non-CO2 GHG-feedbacks. And H&S don't seem to give an estimate of the magnitude of the possible CO2-feedback. Does anyone have a clearer picture on this? How much more warming can we expect in the longer term when the CO2-feedback starts working? And how long would that term be: centuries or more like millennia?
56852. jomamax at 22:10 PM on 10 July 2012
       Michaels and Cato Unwittingly Accept the Climate Threat
       It's not a good idea to compare 'acid rain' to CO2. Combating acid rain and smog meant higher emissions standards for cars, and adding some pollutant sequestering to factories etc. expensive - but doable - with roughly predictable outcomes. There is no such thing as CO2 sequestration that works within economic thresholds. CO2 sequestration uses enormous amounts of energy. Otherwise, capping CO2 would radically increase the price of energy, making it's way into everything you consume. The changes would be drastic and overwhelming - in Europe, where energy prices are high for a variety of reasons - transportation is a problem. Fortunately, they live close to one another, and they can travel by train, or small car. Trains in America would be uneconomical. We live in suburbs, extraburbs, not city centers. We have more extreme weather (in Germany, few people have air-conditioning, though that might be possible in Cali, certainly not in the east). Cap and Trade in any significant fashion would utterly devastate the Economies in North America and many other places. Finally, two things: - First, If you really want to help, instead of [inflamatory snipped] - perhaps you could be working on actual methods for alleviating the problem. As it stands solar, wind and other renewables - do not work in an economical fashion. (I have a friend who works at GE financing the projects) - they don't add up - and never will. After 40 years of R&D and investment, solar is still a mess. If it were economical, Wallmart would be happy to sell panels and they would be on every roof in America. Nuclear Energy could otherwise be relatively clean and safe, if we could determine a means to operate these engines in an alternative matter, our CO2 woes would evaporate. - Second - I must say I appreciate this site very much, however it has done little to debunk my mild skepticism of climate change. In fact - it has only added to my skepticism. In the comment sections of each of the supposed debunking points you'll find some intelligent rebuttal to each of the points. I'm not a climatologist, therefore I can't integrate any new arguments, but I have a strong grasp of logic and I can assure you there is as much bias on this site as any other. There's some classical rhetorical problems on this site, arguments chasing their tails. The 'CO2 trails Temperature' over the 400K period explanations are particularly entertaining in that, however plausible the theory, it is woefully incomplete, and does not match the current rhetoric of climate change within the last 40 years. As an intellectual exercise, I would urge the author to take the position of the devil's advocate, and spend a few weeks debunking climate change as passionately as he is promoting the concept - because your eyes will open to the rather large gaping 'blind spots' in so many of the arguments.
       Moderator Response: [Dikran Marsupial] Inflamatory snipped. Note it is somewhat ironic that you talk of rhetorical problems and then describe explanations as "entertaining" (which comes accross as a rhetorical dismissal of those arguments, without a solid counter-argument). There are many websites where rhetorical argument is allowed, this isn't one of them. Please stick to the science, and please read the comments policy.
56853. Dikran Marsupial at 20:05 PM on 10 July 2012
       It's not us
       jomamax The mass balance argument is correct regardless of how large natural emissions are. It is easy to show why this is true using the savings analogy. Say I share a savings jar with my wife (who represent the natural environment), that is guarded by loyal ninja to make sure only she and I can make deposits and withdrawals. If I put in $16 a month and notice that our savings rise by only $8 a month, then I know that my wife is spending $8 more a month than she is saving. This is true whether she saves $1 a month and spends $9, or if she saves $10 a month and spends $18, or if she saves $100 a month and spends $108, ..., or if she save $1,000,000,000 and spends $1,000,000,008. As it happens, we do know that natural emissions are much larger than anthropogenic emissions. We know this because the residence time of CO2 in the atmosphere is only 4-5 years, which means there must be a very large exchange flux that swaps about 20% of atmospheric CO2 each year with CO2 from the oceans and terrestrial biota. However this exhange is just that, a straight swap of CO2 between reservoirs, and has no effect whatsoever on atmospheric CO2 concentrations. As Murray Salby says, it is only the difference between total emissions and total uptake that matters, and the mass balance equation shows that even if natural emissions are much bigger than anthropogenic emissions, natural uptake is bigger still. This means the natural environment is actively opposing the rise. If you think Julian is right and the absolute magnitude of natural emissions matters (rather than the difference between natural emissions and natural uptake), then it should be possible for you or Julian to come up with a counter example, in the form of values for natural emissions, natural uptake, anthropogenic emissions and the annual rise in CO2, where the natural environment is a net carbon source and the observed rise is less than anthropogenic emissions, and doesn't violate conservation of mass. You will find that you can't. Note I challenged Julian to do so, and he ducked the challenge, and did not reply to my post pointing out that he had ducked the challenge.
56854. Dikran Marsupial at 19:49 PM on 10 July 2012
       Murry Salby's Correlation Conundrum
       @MMM I can see what you are getting at, but the problem is that the analogy is not appropriate because CO2 is not a condensing gas, so there is no limit to the concentration of CO2 that the atmosphere can support (it isn't the temperature of the pool that matters, but the temperature of the air above it). The mass balance argument does not apply to water vapour because there is a limiting factor to the size of the atmospheric reservoir, which is independent of emissions, and much of the atmosphere is pretty near that limit most of the time. It is true that the fluxes between the oceans and atmosphere depend on temperature, so all things being equal, one would expect atmospheric CO2 to rise in a warming world. However, the thing the skeptics normally ignore is that CO2 solubility increases with increasing difference in the partial pressures of CO2 between atmosphere and surface waters. In the real world, all things are not equal, our emissions have caused a difference in partial pressures, which is increasing the oceanic uptake, which more than compensates for the temperature driven change in fluxes. Essentally the mass balance argument establishes that the rise is anthropogenic, but physics is needed to explain why it isn't a temperature driven natural phenomenon.
56855. Mighty Drunken at 18:53 PM on 10 July 2012
       Remote Siberian Lake Holds Clues to Arctic--and Antarctic--Climate Change
       The sentence from the article is ambiguous. "Cores from Lake E go far back in time, almost 30 times farther than Greenland ice cores covering the past 110,000 years." It seems to suggest to me that the Lake E cores go back 110,000 years but I guess what it is actually trying to say is that Greenland ice cores go back 110,000 years and therefore Lake E cores go back up to 3 million years.
56856. Ari Jokimäki at 15:45 PM on 10 July 2012
       New research special - cloud papers 2010-2011
       Thanks for the comments. Note that I only included links to abstracts of these papers. Some of them might have full texts available online, so it might be good idea to do Internet search on the papers you find interesting. #3 jmorpuss: Above list of papers is from 2010 and 2011 only, so I have made no effort to include earlier papers here (as a sidenote, above list also represents only a small fraction of cloud related papers published in 2010-2011). Some of the earlier papers can be found from some cloud related paperlists in my blog: Papers on global cloud cover trends Papers on cloud feedback observations Papers on the non-significant role of cosmic rays in climate
56857. scaddenp at 15:02 PM on 10 July 2012
       Climate's changed before
       Also, look at Fig 3 here. Temperature compared to forcing from albedo and GHG alone. Also, look up PETM. The cause of the CO2 spike is debated but the effect on climate is remarkable.
56858. jmorpuss at 14:53 PM on 10 July 2012
       New research special - cloud papers 2010-2011
       I thought this would fit into cosmic ray section It's a paper accepted back in 2000 http://www.utdallas.edu/physics/pdf/Tin_rev.pdf
56859. Bernard J. at 14:33 PM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       KR.

       We seem to be avoiding the r/K choice 'r' style reproduction crash.

       The fly in the ointment is the human propensity to switch from K to r (and vice versa) when life history determinants change. I was 'raised' in my undergraduate work on MacArthur and Wilson's paradigm, and whilst it's instructive as far as it goes, my PhD and subsequent work underscored for me the importance of overall life history. I sincerely hope that your impression is correct though, and that the underlying factors remain firmly in place. If not, the toe-curling fact is that human numbers will still eventually drop, but with the causative agent being mortality changes rather than fertility limitations. Under such a scenario we're also likely to swing back further into 'r' territory, which will make the resultant decline even more of a tragedy. Again, the fiasco a few weeks ago in Rio, and the essential failure of Copenhagen, do not bode well for our abilities in anything resembling appropriate global management of the farm. One important litmus test for indicating eleventh-hour consciousness-shifting will be whether Australia manages to keep its price on carbon beyond the life of the current government. If not, anything that humans do achieve afterward will be little more than the closing of the barn door...
56860. Bob Loblaw at 14:27 PM on 10 July 2012
       It's not us
       This debate is also going on in the Murray Salby thread. jomamax: you have several "ifs" that are "aren'ts". 1) "black-box may be inserting/removing 1000's every month - you don't know.". Yes, we do know, with a fair degree of accuracy (but not perfectly). The known fluxes in the carbon cycle don't have error bars that large. 2) "If the plus/minus CO2 contributions via sinks/sources from 'non man made sources' (I'n not going to use the proper scientific term since I'm not sure of it's meaning) is rather large, and it varies quite a lot over time". It is large, but it's not varying that much over time - at least, not in amounts that we don't know about (point 1). CO2 was fairly steady (with a seasonal cycle) for a long time before people started burning fossil fuels, and we know a lot about the cycles. 3) "If those net contributions can be definitely characterized as stable and small,". They don't need to be small, and they don't need to be stable for us to have reasonable estimates of them. You'd need to have large, variable errors in the measurements of those fluxes, and that's not the case (point 1). 4) "I'm guessing however, that we don't really understand the size and magnitude of these other heat-sinks". You'd be guessing wrong. (I presume you meant CO2 sinks.) In addition, you have to remember that in the bank balance scenario, you are also using marked bills. Unless the other sources/sinks are marking the bills exactly the same way, the source is obvious. CO2 from fossil fuels is depleted in C14, and has a C12/C13 mix that does not match other sources of CO2 that are depleted in C14.
56861. skywatcher at 14:26 PM on 10 July 2012
       Climate's changed before
       #312: henanlkf, you'll find a lot of great information and good examples of CO2's role in palaeoclimate (geological, Quaternary and more recent) in a presentation given by the great Richard Alley at AGU in 2009: "The Biggest Control Knob: Carbon dioxide in Earth's climate history" He's a really engaging speaker too, so this is well worth your time to watch and listen!
56862. Bob Loblaw at 14:08 PM on 10 July 2012
       Murry Salby's Correlation Conundrum
       Hmmm. Looks like Sphaerica and I are pooling responses... (pun intended).
56863. Bob Loblaw at 14:06 PM on 10 July 2012
       Murry Salby's Correlation Conundrum
       Another pool analogy. I was going to post this in response to marco, but it may also address MMM's points. Suppose you have a large swimming pool. It has a pump/filter system that sucks 100 gallons per minute out of the pool, runs it through a filter, and dumps it back in the pool. It has run for months, and the level of the pool is essentially unchanged. There might have been a bit of evaporative loss, but let's ignore that for now. You then get a garden hose and start adding water to the pool (from the city water supply) at 1 gallon per minute. You say to yourself "it's only a fraction of the amount the filter system is cycling". You walk away, and come back two days later to find that the pool has overflowed. Do you think it is a serious argument that the garden hose can't possibly affect the level of the pool, because it is so much smaller a flow that the filter system? If so, what caused the pool to overflow? That's the argument put forth by the "skeptic" side, when they say the fossil fuel input is insignificant compared to the natural fluxes.
56864. Bob Lacatena at 14:04 PM on 10 July 2012
       Murry Salby's Correlation Conundrum
       MMM, I don't think the analogy works, though, because water vapor is so sensitive to temperature, and will easily condense into the oceans as the temperature drops. CO2 is far more "long lived." Yes, for any individual molecule, it will drop out, but another will take its place. There are only three real places for CO2 to go in the short term, the air, the ocean, and biomatter. Biomatter can only grow so much, and is limited by other factors. The oceans can absorb a lot (and that's a huge problem, too), but not all of it. A better analogy would be two pools, one representing the atmosphere, the other the ocean, and a lot of people lounging around the pool, periodically scooping water out of each in tall glasses to drink it. Then some moron drives up with a huge tanker truck full of water, dumps it all at once and drowns everyone. Now there's an analogy for you.
56865. KR at 13:54 PM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Bernard J. - It is my guess that education and birth control are making their inroads. That is strongly dependent on any number of factors, not the least of which are stability of civil society and the permeation/influence of various cultures by first world TV shows (which show the possibilities of education). However, I have some small hope that the 60 year trend in TFR and the 45 year trend in net reproduction rate (peaked at 1.869 in 1965-1970, now at 1.082) are sustainable directions. It will not be sufficient on it's own to avoid a huge AGW impact, but it's at least one positive note. We seem to be avoiding the r/K choice 'r' style reproduction crash.
56866. Chris McGrath at 13:41 PM on 10 July 2012
       Remote Siberian Lake Holds Clues to Arctic--and Antarctic--Climate Change
       What an amazing paper! The data in figure 3 going back 2.8 million years is mind blowing. By the way, the citation for it is: Melles M, et al (2012) "2.8 Million Years of Arctic Climate Change from Lake El’gygytgyn, NE Russia" Science DOI: 10.1126/science.1222135 The abstract is available at http://www.sciencemag.org/content/early/2012/06/20/science.1222135.abstract?sid=040f10e5-d150-415f-b2de-e92d5db0a635 (subscription required for full article)
56867. KR at 13:40 PM on 10 July 2012
       It's not us
       jomamax - I would have to forcefully disagree. If we know: * We are contributing X to the bank balance * We know the total balance to be increasing at X/2 Then: * Other contributions and deductions from that balance are such that other contributions are X/2 less than deductions; that the other influences on the balance are a net sink. It doesn't matter how much those other contributions/deductions vary in toto - the difference between them is established to be negative X/2 by observing our contributions and the total balance. By knowing how much CO2 we put out and how much the atmospheric levels increase - we know two of the four values, and hence we really do know the difference between the other two. Stable, varying, whatever; it just doesn't matter. We know what the difference is between the natural sinks and sources, and it adds up to about half of our emissions - nature is a net sink. There's just no other way possible to work the math, barring Little Green Men (LGM's) adding or subtracting carbon from the biosphere. And if you make that kind of causal assertion, well, I'm going to feel completely justified at laughing...
56868. Bernard J. at 13:09 PM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       On thinking about it, I realise that my post about the energy policies of the Australian political parties might stray too close to (and overstep) the boundaries of Skeptical Science's own policies. If so, I'm happy for it (and this post) to be removed.
56869. Bernard J. at 13:02 PM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       KR

       Much of that prediction is based on changes in the total fertility rate (TFR) (number of children born per woman over their lifespan, as a statistical average) which is dropping in much of the world. Currently it's at roughly 2.52 globallyo, dropping through 2.36 in the next 5-10 years, down from just under 5 in the 50's.

       Indeed, and the TFRs are one of the parameters that I frequently wonder about. They are (inversely) correlated with education and with energy use, and given the very high probability of the supply of both latter parameters being compromised in the future, it begs the question about whether TFRs will rebound as a consequence. It will be a complicated dance with the degree to which we are able to introduce renewable energy, both in response to climate change and to peaking fossil fuels. Of course, superimposed will be inevitable future shocks to societies, and what the net effects of such shocks are on subsequent population trajectories.
56870. Tom Curtis at 12:42 PM on 10 July 2012
       Nil Illegitimi Carborundum
       david.apell @325, ask and you shall receive.
56871. Bernard J. at 12:42 PM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       

       I have no doubt that in the long term investment in renewables is good for the economy, and in particularly if compared to the difference of the effect of AGW on the economy if we do not invest in renewables. In the short term, however it is a cost.

       If only the two major political parties (and most of the economists) in Australia could be pursuaded to consider the long term in this context, rather than to see no further than the ends of their electoral/annual-bottom-line noses. Yesterday a Labor politician called the Greens the party of the protest vote. It's more likely that the Greens are the only party with clear vision, and the only party with policies that could operate sustainably into the far future.
56872. jomamax at 12:27 PM on 10 July 2012
       It's not us
       Dikran, KR + Julian. I have no background in climate, I'm a computer scientists; loving your debate. KR is correct in saying that since we did add 'xyz' amount of CO2, then it is humans who can be attributed to that amount - but KR/Dikram - Julian is correct to point out that it could be entirely meaningless. KR you are throwing straws on the camel's back, maybe you broke the camels back, Julian is pointing out that your straws - though technically 'added' are irrelevant given that others were adding and removing straws from the camels back by an unknown amount. KR - Julian is not proposing a 'Green Little Man' argument - he's indicating that the other sources/sinks for CO2 could indeed be quite vast. If they are - and they are highly variable - then his assertions are not only correct, but meaningful. You are sharing a bank account with a 'black box'. You know the black box withdraws and adds X amount every month. You know that you add $16 every month. The bank account seems to be rising by ~$16 every month. You know for sure that the 'black box' NET contributions monthly are 0 - but you have no idea why, or what the net attributions are. To KR's point, it is reasonable to conclude that since you are adding $16 every month - well - you are adding $16 every month - no doubt about it. KR is technically correct - but his point may be mute. Julian's point is that the black-box may be inserting/removing 1000's every month - you don't know. If this is the case - then KR your point is mute - it doesn't matter if we are adding $16 a month. Dikram, your analysis would be off. The Dikram/KR/Julian debate boils down to this: If the plus/minus CO2 contributions via sinks/sources from 'non man made sources' (I'n not going to use the proper scientific term since I'm not sure of it's meaning) is rather large, and it varies quite a lot over time - then Julian's position is not only technically correct, but it is very valid. If those net contributions can be definitely characterized as stable and small, then we can safely follow Dirkam's points on the matter and KR's point that 'we are adding X amount every year' matters - because our contributions are meaningful. I'm guessing however, that we don't really understand the size and magnitude of these other heat-sinks, and that they may be highly variable. If this is the case then Julian's point should be considered. KR is technically correct but his point is mute - and Dikram's analysis must be flawed.
56873. david.appell at 12:03 PM on 10 July 2012
       Nil Illegitimi Carborundum
       Excuse me, but how do we know these emails are legitimate? The site they come from is poorly written with no names attached.... Why doesn't the FOI have a cover letter? Every FOI I've ever received has a cover letter showing where the information came from, and from whom....
56874. Tom Curtis at 10:59 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Tony O @41, I have no doubt that in the long term investment in renewables is good for the economy, and in particularly if compared to the difference of the effect of AGW on the economy if we do not invest in renewables. In the short term, however it is a cost. It is a cost because in the sort term it requires more workers for the same level of power production. (I believe in the long term that will reverse.) The economy is a means of allocated limited resources, and the crucial limiting resources are human work, and energy. If we have more people working to generate the same amount of electricity, that means we must pay more for the same amount of electricity - or pay the workers less than they would otherwise have been payed. In either event that is a cost on the economy. In the simplest terms, because those extra workers are producing electricity, it means they are not producing other goods or services that we might otherwise have desired. You may argue that the extra wages come from the money saved by not needing to pay for fuel. That is a fair point, but the cost of the fuel comes from wages paid to extract and transport the fuel (including the costs of building the equipment used for that purpose). So if revenue neutral, ie, the saving in fuel exactly match the increased wages, we are merely substituting wages paid in our nation for wages paid overseas. This is not exact, because there are variations in returns on investment, and variations in wages paid. But the principle is essentially correct and means the equation of more jobs ergo good for the economy does not hold. This issue is different from the question of full employment, which is good for the economy but can be accomplished independently of investment in renewables. Effectively the choice with appropriate economic policy is full employment with renewables and without; and if renewables require more employment for the same electricity supply, full employment without renewables results in more goods and services being produced, and hence is better for the economy.
56875. MMM at 10:57 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       Hi Tom: What I'm trying to do is put myself in the mindset of the closest-to-sane of the contrarians. It is possibly useful to understand their mindset if we have any chance of convincing them, and possibly also to convince the fence-setters. I agree that the Law Dome is a strong argument - I think it has a better chance of standing alone than does the mass balance - you'll see I brought it up in #37. Of course, in combination, the law dome plus mass balance becomes nigh-indisputable. Hmm. The acidity argument might actually work too. At first, I was going to dismiss it based on the "pool" analogy - the pool having more water doesn't change the vapor pressure of the water - but yes, an ocean with higher total-dissolved-carbon does change the "vapor" pressure for CO2 in the atmosphere. -MMM ps. Sphaerica; The analogy is meant to be: pool water = CO2 in the ocean. Humidifier water = fossil fuels. Not a perfect analogy, but pretty close to what I think the Roy's & Salby's and other "sophisticated" contrarians must be thinking...
56876. henanlkf at 10:45 AM on 10 July 2012
       Climate's changed before
       "Greenhouse gas increases have caused climate change many times in Earth’s history", in the article it is amazing to me to listen this news, could you tell me what are the cases of climate change caused by greenhouse gas increasing? what is the status of the greenhouse gas incrasing caused?
56877. Tom Curtis at 10:33 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       MMM @36 the atmosphere and ocean maintain an equilibrium with regard to the vapour pressure of CO2. Therefore, if you increase the concentration, and hence vapour pressure', of CO2 is the atmosphere, the ocean will absorb more CO2. But if you increase the temperature of the ocean the equilibrium ratio will shift, raising the CO2 concentration in the atmosphere In the former case, the acidity of the ocean will increase, in the later the acidity of the ocean will decrease. So, unlike the case in your analogy, we have a simple means to check whether the increase in CO2 is due to increasing emissions or from warming of the ocean. It is the former. Further, we have a simple check of the theory that the rise in CO2 is due to increased temperature. The following is the CO2 record from Law Dome: (Source: Wikipedia) Multiple reconstructions of past temperatures have shown MWP warmth to be comparable to that in the 1950s, with an error range which does not exclude it being as cool as the 1910s or the 2000s. Fake Skeptics are convinced that those reconstructions underestimate MWP temperatures. If follows that if ocean warming is driving CO2 rise, the CO2 levels in the MWP should match current CO2 levels. So while I agree that unique scenarios can be constructed that void the mass balance argument, they do not show that the mass balance argument is faulty. The merely show that it is an inductive rather than a deductive argument, which has arrive at the correct conclusion (as sound inductive arguments typically do).
56878. John Hartz at 10:32 AM on 10 July 2012
       Remote Siberian Lake Holds Clues to Arctic--and Antarctic--Climate Change
       Phillipe: Lake E lies in about the center of Beringia, the largest contiguous landscape in the Arctic to have escaped continental-scale glaciation.
56879. skywatcher at 10:14 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Clyde, you did not answer my question. It is an observed fact that there has ben an observed progressive increase in extreme heat events across the globe over the past 50 years. What is causing that increase? An analogy: Striker V Natural always scores about 20 goals a season for his football club. They are distributed at random through the season, and the club win about half their games in the season, finishing mid-table. The club then sign another striker to play alongside V Natural, called Ant Ropogenic, who starts slowly, scoring only a few goals in his first few seasons, but gradually increasing his scoring rate to more than 20 goals a season. Eventually Earth United are winning more games and ultimately win the league. You are looking at the final scores in the league-winning season, and don't know who scored each goal in each game (just as we can't tease out every specific storm, low presure or blocking high that is caused by AGW). Maybe V Natural scored all the goals? Yet before Ant Ropogenic started playing, the team were mid-table and mediocre. Not so many wins! [ie extreme events] How confident are you that V Natural scored all the goals in the league-winning season? How confident are you, for any one game [any one extreme event], that Ant Ropogenic didn't contribute to the victory? The analogy is far from perfect, but you have to ask yourself, in a world that is warming rapidly, why the observed increase in extremes of high temperature (commonly called heatwaves) would have nothing to do with the forced warming that is going on? From SREX:

       "In many (but not all) regions over the globe with sufficient data, there is medium confidence that the length or number of warm spells or heat waves[3] has increased." "It is likely that anthropogenic influences have led to warming of extreme daily minimum and maximum temperatures at the global scale."

       Your first link is paywalled and the abstract does not contradict Hansen; NOAA in your second link say this, entirely consistent with Hansen:

       "And while the scientists could not attribute the intensity of this particular heat wave to climate change, they found that extreme heat waves are likely to become increasingly frequent in the region in coming decades."

       So NOAA are entirely consistent with Hansen et al. Trying to attribute individual weather events to climate change is a mugs game, but observing the global change in trends is actually quite straightforward. AGW plays a role in determining the pattern of weather events - a pattern that sees episodes of increased heatwaves (e.g. USA now), and increased floods and rain (e.g. UK just now), but patterns that are not static. Maybe next year the UK will suffer a heatwave (it just had a drought too before the spring/summer rains), maybe Washington will be flooded next year. Who knows where the extremes will happen? But I'd bet on the global patterns continuing and intensifying. All consistent with the intesifying water cycle in a warming world. Are you still confident that Texas and Russian heatwaves have nothing to do with climate change?
56880. Bob Lacatena at 10:03 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       16, Clyde, During the first week after a physical has shown that you have cancer you feel fine. So you figure you don't need to do anything about it, and you can let the cancer take its course until it becomes a problem? We've only gotten to 0.8˚C of the 1.4˚C temperature change to which we have already committed, and of the 2˚C to 2.5˚C that we are very, very unlikely (at our current pace of action) to avoid. You really believe that just because current extremes can't be definitively, statistically and un-categorically tied to climate change, that that means that climate change is harmless? Is that really your position? [Please don't bother to answer. The question is rhetorical. I really don't care to hear your response.]
56881. scaddenp at 10:03 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Interesting to perhaps consider that the heatwaves in Russia and US have happened while ENSO ONI index is negative. How ugly would summer be when coinciding with an El Nino event of 1.5 or greater?
56882. Tony O at 09:54 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Tom Curtis @25 Dealing effectively with global warming will not be bad for the economy, on the contrary it will be beneficial. Investment in energy efficiency would be a huge employment creator, hugely beneficial and with a surprising quick payback period. Renewables will also be an employment creator, more than the equivalent investment in coal or nuclear. The required investments can be small scale, local and will increase resilience. They will also give greater independence from the huge global financial companies. There will be no need for the multi level financialization of financialization. One reason renewables are so opposed by people not in the oil and gas industry. What I was saying is that our current economic soccial system is very much more fragile than people understand. Even if the effects of climate change are not that serious it will still be a too big a shock for the system. But the effects of climate change are already guaranteed to be serious.
56883. Bob Lacatena at 09:48 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       MMM, Your analogy thoroughly confuses me. What are your sources of water? In the case of CO2, it's pretty straightforward. The only viable sources and sinks are fossil fuels, biomatter, the oceans and the atmosphere. There's nothing else (there is carbon stored in the deep ocean and such, but it is in stable storage -- just like fossil fuels). There just aren't a lot of places to get the carbon from, or to hide it once it's been sucked from the ground. To violate the mass balance argument, one must show (a) where the 346 Gt of human, fossil-fuel-generated carbon went, (b) where the extra carbon in the atmosphere came from, and (c) why the mass balance, without that extra source of natural carbon, would have been zero otherwise (i.e. why the magical natural carbon increased atmospheric levels while non-magical anthro-carbon would have been sucked into whatever magical carbon sink is holding it). A whole lot has to happen, with a whole lot of carbon, to make any sort of argument that confounds the mass-balance argument. The core of the magical natural carbon source argument comes from the idea that there is so much carbon floating around in the ether that we can't possibly account for it... that volcanoes, oceans, coal fairies, carbon kobolds, petrol pixies and the like can all spread their magical carbon dust wherever they please without us silly, ignorant humans ever noticing.
56884. Philippe Chantreau at 09:24 AM on 10 July 2012
       Remote Siberian Lake Holds Clues to Arctic--and Antarctic--Climate Change
       Interesting article John. Even though it is not the point of the paper, I am curious to know how an Arctic lake could never be covered by glaciers even through the peak glacial times, when an ice cap grip a good part of the Northern hemisphere to lattitudes below 40 degrees.
56885. MMM at 08:54 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       (er: to clarify 36: the world that "sophisticated" contrarians live in - eg, the ones that can get published in E&E - is this short residence time world - many contrarians are in the less sophisticated territory of "natural big, anthropogenic small")
56886. MMM at 07:39 AM on 10 July 2012
       Roy's Risky Regression
       "Figure 8 shows a more realistic (subjective) attribution of the observed increase in atmospheric CO2. " Again, I wholeheartedly agree that the anthropogenic causation of the CO2 rise is (well, "should be") indisputable. Figure 8 isn't, however, an attribution so much as it is a mass-balance. A proper attribution regarding the anthropogenic contribution should tell me what the world would look like if we zeroed out anthropogenic emissions. There are 2 ways of doing that: 1) run a full carbon-cycle-climate model with no human emissions. We'd probably see approximately constant concentration since preindustrial. That gets us about 100% anthropogenic. 2) Run a carbon-cycle model with observed temperatures but no human emissions. I predict you'd see a small rise in CO2 due to the rise in ocean temps - maybe on the order of 5 to 20 ppm. So that would leave about 90% of the rise as anthropogenic (if we ignore the anthropogenic component of ocean heating). -MMM
56887. MMM at 07:27 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       (actually, the other killer argument is the CO2 concentrations are higher than they've been in at least 800,000 years - probably 5+ million years - but that's a hockeystick argument, and contrarians hate those. So then they attack the ice core records...)
56888. MMM at 07:25 AM on 10 July 2012
       Murry Salby's Correlation Conundrum
       First: I agree that the observed CO2 increase is anthropogenic. However, I disagree that conservation of mass is a sufficient argument in and of itself (even though it makes nice intuitive sense). Dikran states: "Conservation of mass is all that is required to demonstrate that the natural environment (i.e. the oceans and terresrtial biosphere) are a net carbon sink. As such it is hard to argue that the observed rise in atmospheric CO2 can be a natural phenomenon when the natural environment is taking more CO2 out of the atmosphere that it puts in." My thought counterexample: I am in a room with a pool. A thermostat controls the pool temperature. I also have a humidifier. I insert X tons of water vapor into the air with the humidifier every year. Every year I raise the temperature of the pool a bit. I measure the water vapor of the atmosphere, and see that it has risen by X/2 every year. Therefore, I know that the atmospheric increase is less than what I have contributed with my humidifier, and that the pool is gaining X/2 tons of water every year. However, that atmospheric increase is NOT due to the humidifier at all! This is because the lifetime of water vapor in the room is short, so any addition of "anthropogenic" water vapor has no impact on long term water vapor abundance, whereas pool temperature does. THIS is the world that contrarians live in: a world where CO2 lifetime is measured in a few years or less. In such a world, CO2 concentration is controlled mainly by temperature, not by anthropogenic additions. Adding in isotope data isn't a magic bullet either because while the perturbation lifetime of CO2 is long, the atmospheric lifetime is indeed on the order of a few years. (contrarians can also try the smokescreen that oceanic carbon is old and 14C depleted, but then they have problems with 13C - but the 13C signal is more subtle). In my opinion, the key point that makes the whole story fit together is the Revelle factor, and how when you incorporate the Revelle factor, carbon cycle models can do a good job of reproducing observations of multiple isotopes. But that's harder to explain in 3 sentences, especially because there are still some open questions on some facets of the carbon cycle, and contrarians don't understand "we understand the system well enough to say X, even though we can't pin down Y yet". -MMM
56889. DSL at 07:05 AM on 10 July 2012
       New research special - cloud papers 2010-2011
       Ari, I really appreciate the work. It is a tremendous help when out in the trenches trying to convince people that they do have time and brains enough to engage the science. It's often just extremely difficult to push them over that gap between assuming understanding and engaging in the learning process. Assumption is so comfortable. Yet when the summary is there right in front of you, it's also tough not to indulge in curiosity and begin walking the path (SkS is the best walking stick in climate science).
56890. Composer99 at 06:04 AM on 10 July 2012
       New research special - cloud papers 2010-2011
       Lots of great stuff in here. Makes me wish I had subscriptions to all these journals.
56891. Rob Painting at 05:43 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Clyde - it is doubtful science is sufficiently advanced to attribute specific heat events solely to natural variability. To do so one would need to tease out the man-made global warming signal which is responsible for warming the ocean basins and increasing the water vapour holding capacity of the atmosphere - two crucial components in the transport of energy around the planet, and therefore important to weather. How does one apportion blame solely to natural variability when the entire planet, and consequently all weather, is affected by global warming? And importantly, the studies need to examine upstream/downstream phenomena which may have contributed to blocking patterns. Indeed, some research suggests blocking patterns become more persistent at the Earth warms. See SkS post: Linking Weird Weather to Rapid Warming of the Arctic Whilst the science of attributing specific events to global warming/natural variability is in its infancy, the statistical basis for the expectation of increased frequency and severity of record-breaking warm extremes is both well-founded and easy enough to understand. You simply need to read, absorb and understand the links that were provided to you earlier. And one final point, the work by NASA scientists Hansen, Sato & Ruedy are simply observations of the GISS temperature record. The increase in the extreme warm events (3 sigma) are a historical fact.
56892. Clyde at 04:17 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       skywatcher 30 perhaps you can answer the question as to why heatwaves such as the one the USA is experiencing (and, for example, Texas last year, and Russia the year before) I did not write the IPCC SREX. It's my understanding the IPCC is the big chief so to speak on GW matters. “Long-term trends in economic disaster losses adjusted for wealth and population increases have not been attributed to climate change, but a role for climate change has not been excluded (medium evidence, high agreement).” You use one paper from Mr Hansen to suggest the IPCC SREX is wrong. Richard Klein might disagree with your point. He "scolds" some guy named Joe Romm for misrepresenting the findings. Read more here. one. Several studies show that the anomalous long-lasting Russian heat wave in summer 2010, linked to a long-persistent blocking high, appears as a result of natural atmospheric variability. two. The deadly Russian heat wave of 2010 was due to a natural atmospheric phenomenon often associated with weather extremes, according to a new NOAA study. Two papers that disagree with Mr Hansen. GW had little to do with the Russian heatwave.
56893. KR at 03:50 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Bernard J. - The 10.1-10.2 mid-line level is about what I've been seeing in predictions too. Much of that prediction is based on changes in the total fertility rate (TFR) (number of children born per woman over their lifespan, as a statistical average) which is dropping in much of the world. Currently it's at roughly 2.52 globallyo, dropping through 2.36 in the next 5-10 years, down from just under 5 in the 50's. In first world countries the replacement rate for stable population is ~2.1, while for developing countries it's between 2.5-3.3 due to higher mortality. However: I feel you are completely correct about the 'wheels falling off' prior to a population peak. The impacts on agriculture alone will impose additional constraints on populations. And the longer we wait, the worse it will be.
56894. Bernard J. at 03:42 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Tom and dana. I recognise that my points are not specifically about addressing climate change in order to avoid a global 'screwing', and I do apologise if they are shifting the topic somewhat, but I feel that they are important in gauging the overall measuring of the collective actions required to address the sum total of the challenges the world faces. If you'd prefer, I'm happy to carry the conversation to another thread.
56895. Bernard J. at 03:26 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       KR. As the graph below indicates the UN mid-range estimate for the global human population at 2100 is around 10.1 to 10.2 billion. I suspect that this is predicated on a complex range of assumptions, some of which are unlikely to hold for that long, including the reaching of no significant limits of essential resources. However, for my previous comment where the underlying assumption of the discussion was that energy availability is not a limit, I assumed that other limits usually taken to impinge on the mid-range human population growth estimate would be pushed back ever so slightly as a consequence of this energy bounty, and thus that a 50% increase to 10.5 billion was a good ball-park. I did this primarily to put the relative proportions of resource use into easy context for the post, and given current trends and an assumption of no resource limits I'd say that there would be a better than even chance of it occurring. In truth, I strongly suspect that the wheels to which I referred on the aforementioned wagon will have well and truly fallen off before 2100. In fact I suspect that the actual number will be much less than 9 billion - and the thing to keep in mind in that scenario is that the change in trajectory will occur with much 'premature' death, and with the accompanying anguished tragedy and economic and social damage that would inevitably occur at that scale. A growth curve simply does not change to that extent without serious intervention in population trajectories in at least a big proportion of the world's nations, and if that intervention is not premature death it would be greatly reduced fertility, which would most likely come from government-imposed reproductive austerity. This is the 'nice' view though: more likely it will be disease, famine and war that ride shotgun to the excess deaths, as a consequence of the factors to which I pessimistically referred in my post at #34. The abject failure of the Rio summit just over a week ago is, in my book, the final nail in the coffin, the straw that will break the camel's back... That the world's governments could not only not act at this point in time, but that they did in fact abdicate all pretense at moving to sustainability, signals that the time has passed for serious addressing of the world's environmental problems before significant damage occurs.
56896. KR at 02:33 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Regarding population growth - Most of the estimates I've seen (such as this 2004 UN report) indicate that we'll probably peak at a population of 9-10 billion late in the 21st century, with a slow decline afterwards, based upon decreasing birth rates and aging populations. "Peak population" is in sight. Of course, when I was born the world population was ~4B, and we're currently over 7B; 9-10B is a huge increase, with a huge impact. It seems unlikely to me that we'll ever have the entire world population at a point where it can use energy at the level the US or other first world countries now do - but I do expect that the development of renewables will provide a pathway to increasing the total energy available to the world, with benefits accruing for the average person everywhere. If, of course, we manage not to destroy our agriculture before cutting off the carbon emissions...
56897. Bernard J. at 01:25 AM on 10 July 2012
       Climate change is simple: We do something or we’re screwed
       Tom.

       Bernard J @32, eco-system degradation is certainly a problem, but it is a distinct problem from global warming.

       Not entirely, as the effects of global warming will seriously exacerbate ecosystem degradation. But that's a little beside my original point, which is that providing abundant renewable energy to replace fossil energy will not solve all of the problems that beset our society and the biosphere. And in solving the problem of fossil-fueled energy sources, we need to be cognisant of not adding to ecosystem degradation in other ways.

       More importantly, it is a simple fact about human nature that you will not persuade them to downsize their demand.

       Sadly, in the context of its consequences, I very much concur with you on this point. However, a corollary of this fact is that you are just as unlikely to see humans give up their wonderful new and renewable sources of energy for use in exploiting the rest of the planet's resources. Even if desalination could provide at an environmentally neutral cost limitless water for hydroponic vegetable growth, again at an environmentally neutral cost, it's not going to happen in the next century at a scale that is going to supply food to the planet. And if it does, it won't satisfy the global appetite for meat, which correlates closely with wealth (and hence with energy use), so the pressures on soils would remain and likely increase in rate, essentially in fulfilment of Jevon's paradox. Further, there is no simple quick fix to fish stock over-exploitation, and there is no quick fix to the clearing of forests in many parts of the world. Abundant renewable energy won't reverse urban/suburban sprawl that follows energy wealth - again, it's Jevon's paradox. And a lot of that sprawl occurs in biodiversity-rich areas, so once more the pressure on ecology is not relieved. Abundant renewable energy will not slow, for decades at least, the trajectory of population growth: this is already set by the demographic structures of countries with growing populations and with little prospect of the imminent appearance of wealth, and the cultural sequelæ that follow wealth and that would otherwise put the brakes on further growth. So, with a population that is likely to be at least 50% greater than it is now by the end of the century, should the wheels not fall off the wagon before then, we would have billions more people expecting to live lives enriched by at least as much energy (and concommitant non-energy resource use) as we Westerners use now. Even if we assume that future non-energy resource use somehow decreases even as we continue to use energy, we'd need to decrease our non-energy resource use by an average of two thirds with that 50% population increase, to remain at the current (unsustainable) levels. Further, abundant renewable energy will very likely increase the complexity of the global societal and technological systems, and there is a whole discipline that recognises the vulnerability of complex systems to catastrophic failure. In the 'natural world' such failure is part and parcel of creating eventual resilience over evolutionary timescales via the mechanism of survival of the fittest. Nature red in tooth and claw, as it were... When inevitable failures of human systems occur there is damage, as we've seen in history, but a future society built to even more complexity using limitless energy, in a world damaged by previous over-exploitation, will see failures of a magnitude that would not be countenanced if we could know of them beforehand. Some might argue that we have resilience already, or how could 'it' all work as it does, but the very fact that our society is not in balance with the biosphere contradicts that notion. The very fact that our society has wobbled from are really minor financial crises contradicts that notion, and the fact that there are not-so-small hurdles on the horizon such as the intractable US debt contradicts that notion. And this is beside the flaps that our societies are currently having about Peak Oil and climate change. I'm not saying that renewables are not desperately required. They most certainly are. However, they are only a part of a solution, and of a solution that needs to be found and enacted quickly, before thermodynamics take matters into its own hands. Humanity's unbalance with the planet on which it lives is like a chain. Reinforcing one weak link - energy - isn't necessarily going to prevent breakages elsewhere in the chain, and if doing so means that we believe that we can continue hauling the same overload as in the past, then we're still going to have catastrophic failure somewhere in the chain. In other threads there are emphases on the conservation of energy, and on mass balance. The very same thermodynamic principles apply to all human activity within the biolithohydrosphere. You are correct to point out that our human nature contrains how we respond to problems, but thermodynamics is an even tighter contraint on the final results of our responses. If we can't prune our impact to live within the limits of the planet, the planet's limits will do it for us. Sadly, that outcome should it eventuate will be disasterous for many millions (even billions?) of humans,and most of those will be people who were never responsible for the problems in the first place. And in that alternative outcome, even hair shirts may be a luxury.
56898. Bob Lacatena at 01:22 AM on 10 July 2012
       Ian Plimer Pens Aussie Geologist Gish Gallop #2 of the Week
       dissembly,

       A carbon price resembles a flat tax (like the GST) more than it resembles a progressive tax (like income tax); which means it will affect you more by a disproportionately greater amount the further down the income scale you go.

       This is true of everyone, everywhere, and it will be true of climate change whether the problem is addressed or not. The people who will starve, become refugees, or just plain see their quality of life dissolve will be the poor. And, to a lesser extent but still a lot, the middle class. The people who will still eat well, jet around the world, live in climate controlled houses, etc. will be the rich. Mind you, a lot of people who are rich are going to see their fortunes evaporate and join the ranks of the poor. One aspect of climate change, whether handled through adaptation or mitigation, is going to be the complete reshuffling of wealth. Today's wine-grower in California or beach-front property owner is tomorrows useless-parched-land-owner or useless-underwater-land-owner. Things will change, and many of the rich who are resisting change now are going to suffer for it. But, for the most part, they'll be fine. It is the poor, average folk that you say are so fearful of being taxed who are going to lose one way or the other, either a little by investing some of their money into addressing the problem, or a lot by ignoring the problem and watching their lifestyles change in unimaginable ways. Really, climate change is just the grasshopper and the ant fable, all over again, but in this case it's not hard work that the grasshopper needs, but rather choosing to do the right hard work, and accepting that you need to do and invest your energy in what must be done, not what you wish will be lucrative, or what has always in the past been lucrative.
56899. Bob Lacatena at 01:15 AM on 10 July 2012
       Ian Plimer Pens Aussie Geologist Gish Gallop #2 of the Week
       dissembly, Honestly, you write so much with no clear statement of point or purpose that it's hard to follow exactly what you are arguing for, but the bottom line is this: 1) In the USA, people are programmed to shake in fear at the word "tax." 2) In the USA, people are programmed to believe that because "we won the cold war" that capitalism is God and any problem is best solved through the free market. 3) Carbon has a large, hidden cost to society which does not affect the seller or the user directly. 4) Because of these hidden costs, there are some things that governments must accept as within their sphere of influence because the free market has no way of addressing or even recognizing them. This has always been the case in any society in terms of the common defense, fire/police/emergency provisions, foreign commerce, education, regulation and law, and other things. There are simply things that the government must do. A carbon price is an attempt to address all of these issues... to avoid the fear of taxation, to allow the free market the maximum flexibility in addressing the problem (rather than the government-bureaucratic-5-year-plan-Soviet-style solution), to make sure that that hidden cost does affect both the supplier and user directly, because it is being paid by someone, eventually and last of all to make sure that the problem is engaged and not simply ignored because people don't want to think about it until it's too late. Imagine a world where you have no army or navy because you don't want to pay the tax that provides for it. That's great until you are invaded. Imagine a town where you have no police or fire department, because you don't want to pay the tax that provides for it. That's great until you are robbed, murdered or watch your house burn to the ground. Things need to get done. Money is the lever in all of today's society. Supply and demand and exchanges are how money is allocated to problems in the free market. Taxes, tariffs, fees and markets are how money is allocated (or re-allocated or funneled) to problems by governments. Not all problems are "how do we make, transport and market more widgets at lower prices, so that everyone in the world can enjoy a vast collection of widgets." You can argue all you want about the mechanics behind the best possible solution, but it must address all of these 4 factors, and many others, and in the end it has to work, and it has to get started soon, because the longer it takes, the less it matters exactly what you do and the more you will be forced to live with something even worse than you expected, simply because you took too long to get started.
56900. dana1981 at 00:57 AM on 10 July 2012
       Michaels and Cato Unwittingly Accept the Climate Threat
       Mark, I presume Michaels would argue that drug development is one way we've adapted to various diseases. For example, they want to adapt to increasing heat waves by installing more air conditioning units and other similar infrastructure. The logic is that instead of preventing the problem, you adapt to it. My analogy was that instead of reducing gun violence, you just hand out bullet proof vests.

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